This program project focuses on immunologic events that trigger, sustain, or dampen immune responses in[unreadable] tissues, including: 1) the skin in graft versus host disease (GVHD); 2) the gastrointestinal tract in[unreadable] inflammatory bowel disease (IBD) and GVHD; and 3) the heart, in cardiac allografts with chronic rejection.[unreadable] This core will be directed by A.J. Demetris, M.D; who has extensive experience in these areas and will be[unreadable] responsible for assuring that the principal roles of the core are fulfilled. The principal roles are to:[unreadable] A) Grade and stage each of the inflammatory diseases, described above, which are important endpoints for[unreadable] each of the three projects.[unreadable] B) Use detailed tissue sample analysis to help understand immunologic mechanisms contributing to, or[unreadable] preventing, the inflammation, tissue damage, and structural alterations.[unreadable] The core is designed and ideally situated to accomplish these goals as we have successfully fulfilled similar[unreadable] functions for more than 15 years at the Thomas E. Starzl Transplantation Institute. The laboratory utilized for[unreadable] the Histopathology Core is already fully functional and equipped to conduct routine and specialized tissue[unreadable] triage and analysis techniques, including grading and staging of inflammatory disease processes,[unreadable] characterization of cell phenotypes (and subtypes), and their interactions within systems. Furthermore, our[unreadable] considerable experience in computerized image processing and morphometry will enable quantitative[unreadable] analysis of observed phenomena to corroborate earlier, possibly quite subtle, qualitative changes. In[unreadable] addition, we have the capability to communicate results/data to off-site investigators using pre-existing whole[unreadable] slide digital imaging capabilities and telepathology software already in use for other projects in our[unreadable] laboratories.